Switch and method for switching a high-voltage connection

Abstract

The invention relates to a switch (1) for switching a high-voltage connection, comprising at least one fixed contact (2) and at least one movable contact (3) in a housing having a housing base (10) and a housing cover (11), wherein the movable contact (3) is secured to a support unit and is guided in a part of the housing, and the fixed contact (2), the housing base (10), the housing cover (11), and the support unit form a switching chamber (12) which is under atmospheric pressure in the open state of the switch (1) and is sealed against atmospheric pressure in the closed state of the switch (1).

Description

[0001] Switches and methods for switching a high-voltage

[0002] The invention relates to a switch for switching a high-voltage connection with at least one fixed contact and at least one movable contact in a housing.

[0003] The invention also relates to a method for switching a high-voltage connection.

[0004] State of the art

[0005] High-voltage contactors or high-voltage switches, as used in every state-of-the-art electric vehicle, are capable of switching under load and interrupting high currents up to 2,000 A. During switching, an electric arc is generated which must be extinguished as quickly as possible. High-voltage contactors in automotive applications open and close by moving a movable contact element linearly to a stationary contact. It is known that the entire contact chamber is filled with a working fluid such as hydrogen under a certain pressure. The entire unit is hermetically sealed to the outside.

[0006] An example is known from US Patent 7,852,178 B1. The switch may include an evacuation port in fluid communication with a chamber of an enclosure to remove gas from the enclosure chamber and / or introduce gas into the chamber. In particular, the enclosure chamber, after being hermetically sealed, may be evacuated to a partial or complete vacuum using the evacuation port. Alternatively, the evacuation port may be used to introduce any suitable inert and / or insulating gas into the chamber, such as hydrogen, nitrogen, and / or sulfur hexafluoride, once the chamber is hermetically sealed. The chamber may be filled with gas to a suitable pressure. Evacuating the chamber to a partial or complete vacuum or introducing gas is possible.

[0007] Introducing an inert and / or insulating gas into the chamber (2024P00107WO) can facilitate the suppression of arcing within the chamber. Once the chamber is evacuated or filled, the evacuation port can be clamped or sealed to maintain the hermetic seal.

[0008] Recently, high-voltage contactors have been installed that forgo this sealing and are designed as open switching systems. The surrounding medium is then air. These switching systems must be moved very quickly, and further measures are implemented to safely extinguish any arcing that occurs.

[0009] A high dynamic range, meaning a rapid opening of the contact over a certain distance, serves to extinguish the arc more quickly. However, this dynamic range is limited by the corresponding inertia and the restoring force of an integrated return spring.

[0010] The object of the invention is to propose a switching system that has optimized dynamics through pressure- and spring-assisted switching.

[0011] Description of the invention

[0012] The problem is solved with a switch for switching a high-voltage connection with at least one fixed contact and at least one movable contact in a housing, wherein the movable contact is attached to a carrier unit and guided in a part of the housing, and the fixed contact, the housing and the carrier unit form a switching chamber which is at atmospheric pressure when the switch is open and is sealed against atmospheric pressure when the switch is closed.

[0013] The arc created when the switch is opened increases the pressure in the sealed switching chamber.

[0014] 2024P00107WO The housing base and housing cover can also be made from one piece.

[0015] The carrier unit is movable due to the pressure in the switching chamber, thereby revealing ventilation openings that restore atmospheric pressure.

[0016] It's not necessary to direct the flow of the medium to the outside; the switching chamber can also be sealed on the inside. This means that, in the case of conventional relays, the openings would lead into the interior of the relay and allow the pressure to escape.

[0017] The carrier unit consists of a carrier plate and a plunger with a spring assembly.

[0018] The carrier unit has a guide pin that moves within a housing guide of the housing.

[0019] The housing guide is designed to be open or closed.

[0020] The problem is also solved by a method for opening a switch of a high-voltage connection, whereby the heat input of an electric arc is used to increase the pressure in a switching chamber when the contacts are opened.

[0021] The pressure in the switching chamber, together with the pressure of the return spring, moves the carrier unit to open.

[0022] Additional pressure is used in a closed housing guide to open the switch. The medium within the guide chamber cannot escape, thus increasing the pressure. This additional pressure is available when the contact opens.

[0023] The method involves assisted opening of the contact by targeted pressure increase of the air within a switching chamber.

[0024] 2024P00107WO To increase the dynamics, especially in open systems without an additional working medium, during opening, the pressure increase of the air medium is utilized. The resulting electric arc locally traps and heats the air in a working area through a suitable sealing device. This heating of the air leads to a pressure increase within the space. Since the air cannot initially escape, the force acts, among other things, on the moving contact, further accelerating it during the opening movement. This increases the dynamics of the contact opening and ensures reliable arc extinguishing.

[0025] The increased dynamics ensure that the resulting arc can be extinguished quickly and reliably. The principle also works when opening without a load, as the dynamics are not crucial in this case and the restoring force of the return spring is sufficient.

[0026] Additionally, the implemented chamber geometry and sealing mechanisms support the extinguishing of the arc at high altitudes.

[0027] Description of the characters

[0028] Figure 1 shows a first embodiment with the switch open, Figure 2 shows the first embodiment with the switch closed, Figure 3 shows a second embodiment with the switch closed.

[0029] Figure 1 shows a switch 1 according to the invention, which is housed in a casing with a casing base 10 and a casing cover 11. The switch essentially consists of a fixed contact 2 and a movable contact 3. The fixed contact 2 has a central opening in which a plunger 7 can be guided, or is already constructed in two parts. The casing cover 11 holds the fixed contacts 2 at its upper surface 2b. The plunger 7 carries a

[0030] 2024P00107WO Spring assembly 8 and an extension as a guide pin 7a, as well as a carrier plate 5 on which the two-part movable contact 3 is mounted. The movable contact 3 has an extension that is adapted to the fixed contact 2. The movable contact 3 also has a gap in the middle between the two contacts 3, which is bridged by the carrier plate 5.

[0031] The carrier plate 5 supports the guide pin 7a of the plunger 7. This guide pin 7a of the plunger 7 guides a return spring 9, which encompasses the guide pin 7a. The return spring 9 rests against the carrier plate 5 and against the underside 11a of the housing cover 11.

[0032] The housing cover 11 has a recess forming a housing guide 13 in which the guide pin 7a of the plunger 7 can move slidably. The housing guide 13 is open to the outside. The housing 10 has ventilation openings 4 which, when the switch is open, are not covered by the carrier plate 5 and the movable contacts 3. A switching chamber 12 is formed in the housing 10. The walls 10a, 10b of the housing base 10, the carrier plate 5 with the movable contacts 3 and the underside 2a of the fixed contacts 2, and the housing cover 11 with its lower boundary 11a form a closed space.

[0033] The switching chamber 12 thus formed has normal atmospheric pressure.

[0034] Figure 2 shows the situation with a closed contact that has a temporarily sealed switching chamber 12. For this purpose, seals such as geometric gap seals, O-rings or sealing lips are installed on suitable components, primarily on the movable contact 3.

[0035] In the embodiment shown, seals 6 are located on the carrier plate 5, and seals 14 are located on the guide pin 7a of the plunger.

[0036] If the plunger 7 in Figure 2 moves upwards, the support plate 5 with the movable contact 3 is also moved upwards, whereby the

[0037] 2024P00107WO Seals 6 on the carrier plate 5 above the ventilation openings 4 can close the switching chamber 12. The housing guide 13 is sealed against external air pressure by the seals 14 on the guide pin 7a of the plunger 7.

[0038] The switching chamber 12 is closed above the contact points so that a pressure force can be applied to the upper side of the movable contact 3. As soon as the contact opens, the movable contact 3 opens depending on the restoring force of the return spring 9 and the corresponding inertia of the contact. Under load, an electric arc 15 is generated, which heats the air in the switching chamber 12. The pressure force D1 is higher when heated by the electric arc than the counter-pressure Da due to atmospheric pressure on the underside of the movable contact 2 against the carrier plate 5. The pressure D1 generates an additional force component in the opening direction, relative to the spring force of the return spring 9, and assists the opening.

[0039] After a defined distance, during which the arc 15 is extinguished, the seal 6 on the carrier plate 5 of the movable contact 3 slips over the ventilation openings 4. Through these, the internal pressure of the switching chamber 12 is selectively reduced, so that the internal pressure in the switching chamber 12 again corresponds to the atmospheric pressure Da and does not oppose the movement when the contact closes.

[0040] The invention can be implemented in a switching system or switching matrix, such as described in DE 10 2023 206 666 B3, using a conventional relay with an electric solenoid coil, actuated relay or switch, as well as a relay guided by a camshaft.

[0041] 2024P00107WO In a second variant, the guide pin 7a can be used as a piston, as in an air pump, to increase the air pressure in a second chamber, the housing guide 13. For this purpose, the housing guide 13 is designed as a closed chamber.

[0042] When the contact closes, the air in this additional space is also compressed. This overpressure Dz and the resulting force are additionally available to the movable contact 3 when opening.

[0043] 2024P00107WQ Reference numeral list

[0044] 1 switch

[0045] 2 fixed contacts

[0046] 2a Underside fixed contact

[0047] 2b Top side fixed contact

[0048] 3 movable contacts

[0049] 4 ventilation openings

[0050] 5 Carrier plate

[0051] 6 Seal on carrier plate

[0052] 7 pestles

[0053] 7a Guide pin plunger

[0054] 8 spring pack

[0055] 9 Return spring

[0056] 10 Case base

[0057] 10a, 10b Walls Housing base

[0058] 11 Housing cover

[0059] 11 a Underside of housing cover

[0060] 12 Switching chamber

[0061] 13 Housing guide

[0062] 13a closed housing guide

[0063] 14 Seal plunger

[0064] 15 arcs

[0065] 2024P00107WO

Claims

9 Claims 1. Switch (1 ) for switching a high-voltage connection with at least one fixed contact (2) and at least one movable contact (3) in a housing with a housing base (10) and housing cover (11), wherein the movable contact (3) is attached to a carrier unit and guided in a part of the housing and the fixed contact (2), the housing base (10) and housing cover (11) and the carrier unit form a switching chamber (12) which is at atmospheric pressure when the switch (1) is open and is sealed against atmospheric pressure when the switch (1) is closed.

2. Switch (1 ) according to claim 1 , characterized in that the arc (15) generated when the switch (1 ) is opened increases the pressure (D1 ) in the sealed switching chamber (12).

3. Switch (1 ) according to claim 1 or 2, characterized in that the carrier unit is displaceable by the pressure (D1 ) in the switching chamber (12) and thereby releases ventilation openings (4) to the outside or to the inside, which restore atmospheric pressure.

4. Switch (1 ) according to one of the preceding claims, characterized in that the carrier unit consists of a carrier plate (5) and a plunger (7) with spring assembly (8).

5. Switch (1 ) according to one of the preceding claims, characterized in that the carrier unit has a guide pin (7a) which moves in a housing guide (13) of the housing.

6. Switch (1 ) according to claim 5, characterized in that the housing guide (13) is designed to be open or closed. 2024P00107WO 7. Method for opening a switch (1) of a high-voltage connection according to one of the preceding claims, wherein, when opening the contacts, the heat input of an electric arc (15) is used to increase the pressure (D1) in a switching chamber (12).

8. Method according to claim 7, wherein the pressure in the switching chamber (12) together with the pressure of a return spring (9) displaces the carrier unit to open.

9. Method according to claim 7 or 8, characterized in that an additional pressure (Dz) in a closed housing guide (13) is used to open the switch (1 ). 2024P00107WQ

Images